I see it this way: if someone is going to be THAT negative about Harry Potter, USH as a whole, or any other aspect or intellectual property at USH, then either don't visit that specific attraction or the park. Simple as that. That applies to Disney as well. There's "opinions" and "not being a fan" of something, and then there's just bashing...
Even I wasn't ever that negative towards Simpsons, and I'm not a fan of the ride.